Abstract: A deployment and retrieval apparatus for ocean bottom seismic receivers, the apparatus being a remotely operated vehicle (ROV) having a carrier attached thereto and carrying a plurality of receivers. The carrier comprises a frame in which is mounted a structure for seating and releasing said receivers. The structure may comprise a movable carousel or a movable conveyor or fixed parallel rails or a barrel. The structure includes a discharge port on said frame and a discharge mechanism for removing and retrieving said receivers. A method for deployment and retrieval of ocean bottom seismic receivers comprises the steps of loading a carrier with a plurality of receivers, attaching said carrier to an ROV, utilizing said ROV to transport the carrier from a surface vessel to a position adjacent the seabed and thereafter utilizing said ROV to remove receivers from said carrier and place the receivers on the seabed.

Abstract: A variable phase valve timing assembly for an internal combustion engine. A camshaft driven by a rotating crankshaft of the invention actuates an intermediate member such as a pivotally mounted lever a bucket tappet a first portion of which bears against a cam supported by the camshaft and a second portion of which bears against a valve of the engine such that rotation of the camshaft displaces the intermediate member and valve in a cyclical manner. The camshaft is displaceable relative to the intermediate member along a predetermined path, and means are provided for displacing the camshaft in dependence upon a control input, for example engine speed. The geometry of the predetermined path and of the first portion of the intermediate member are such that movement of the camshaft alters the phase of displacements of the valve relative to rotation of the engine.

Abstract: A driving connection between a hollow camshaft (1) and its driving shaft (5) located within it, the axes (3, 8) of these two members being parallel but laterally displaceable to vary the characteristics of rotation of the camshaft in response to constant-speed rotation of the driving shaft. The camshaft supports a slideway (11) in which moves a slider (12) which makes a rotary joint with the end of an arm (15) carried by the driving shaft. The geometry of the arm is such that the center of rotation (18) of the rotary joint lies within the outline of the periphery of the driving shaft (5) when viewed along its axis (8), thus promoting radial compactness. The essential component of the arm may be an item (15) of crescent-shaped cross-section, the concave surface (19) of the crescent registering with the surface of the driving shaft.

Abstract: A driving connection between a first and hollow shaft (1) and a second shaft (3) within it, the axes (19, 20) of the two shafts being parallel at all times. By relative radial displacement of the two axes, the first shaft rotates at a variable and fluctuating speed within each revolution in response to uniform rotation of the second shaft. The ball (36) or part-cylindrical (22) end of a radial arm (2), carried by the second shaft, engages rotatably with a recess (37, 31) in a block (4) movable in a radial slideway (23) formed on the first shaft. Axial compactness is promoted by the arm, block and slideway all lying in a common radial plane (30), and radial compactness by the manner of engagement between the arm end (36, 22) and the corresponding recess (37, 31). The invention finds particular use where the first shaft (1) is the camshaft of an internal combustion engine, and in which the relative movement of the shaft axes (19, 20) may therefore be used to vary the timing of the engine valves (7, 8).

Abstract: A balancing system for use in for example a motorcycle engine to balance forces generated by a piston and connecting rod arrangement connected to a crankshaft. The crankshaft supports a first gear meshing with a second internal gear supported by an intermediate member such that the intermediate member rotates in the same direction as the crankshaft. The intermediate member supports a third external gear driving one or more balance shafts. In a single balance shaft arrangement, the external gear drives the balance shaft directly. In a twin balance shaft arrangement, the external gear drives one of the balance shafts directly and drives the other balance shaft via a further gear supported by a further intermediate member.

Abstract: An internal combustion engine having at least one cylinder with inlet and exhaust valves operated via rocker arms by respective cams carried by a single camshaft. The camshaft is connected to its drive by an eccentric linkage, the eccentricity of which is varied by a device responsive to engine speed, and is least at high speed. As engine speed falls, increasing eccentricity results in a relative advance of inlet valve closing time and relative retardation of exhaust and inlet valve opening times but little change in the timing of exhaust valve closure. The lift of the valves may be varied also if the rocker arm axes are movably mounted.

Abstract: A variable valve timing mechanism for an internal combustion engine including at least one valve-actuating camshaft driven from a crankshft is described. The valve timing mechanism comprises a movable member which is arranged in use to be rotatable by the crankshaft and movable in translation relative to the camshaft in dependence upon an engine operating condition such as engine load or speed. The movable member is connected to the camshaft by an eccentric linkage such that movement of the movable member relative to the camshaft varies the angular position of the camshaft relative to the crank and also varies the rate of angular movement of the camshaft, thereby varying the valve timing.

Abstract: A variable valve timing mechanism for an internal combustion engine including at least one valve-actuating camshaft driven from a crankshaft is described. The valve timing mechanism comprises a movable member which is arranged in use to be rotatable by the crankshaft and movable in translation relative to the camshaft in dependence upon an engine operating condition such as engine load or speed. The movable member is connected to the crankshaft by an eccentric linkage such that movement of the movable member relative to the camshaft varies the angular position of the camshaft relative to the crank and also varies the rate of angular movement of the camshaft, thereby varying the valve timing.